1. Technical Field
Various embodiments of the present disclosure relate to methods of fabricating semiconductor devices and, more particularly, to methods of forming patterns.
2. Related Art
As the semiconductor industry rapidly grows, a lot of effort has been focused on realizing integrated circuits having a high integration density. In order to increase the integration density of semiconductor devices comprised of the integrated circuits, it may be necessary to reduce an area that a unit cell of the semiconductor devices occupies and to increase the number of discrete devices for example, transistors, resistors, capacitors or the like integrated in a limited area of a semiconductor substrate. Various techniques have been attempted to realize fine pattern structures having a nano-scale critical dimension (CD), such as, a size of about a few nanometers to about several tens of nanometers.
In the event that nano-scale fine patterns of the semiconductor devices are formed using only a photolithography process, there may be some limitations in forming the fine patterns due to image resolution limits of lithography apparatuses used in the photolithography process. Methods of forming the fine patterns using a self-assembly characteristic of polymer molecules may be considered as a candidate for overcoming the image resolution limits which are due to the nature of optical systems used in the photolithography process and due to wavelengths of lights generated from light sources of the optical systems used in the photolithography process. However, it may be difficult to form fine patterns, which are irregularly arrayed, using a direct self-assembly (DSA) characteristic of polymer molecules. Accordingly, it may be necessary to further develop methods of forming the fine patterns using the DSA characteristic of the polymer molecules to overcome the demerits of the DSA technology.